Optical vortex tracking studies of a horizontal axis wind turbine in yaw using laser-sheet, flow visualisation

Experimental studies have been conducted on a 0.9 m diameter, horizontal axis wind turbine (HAWT) placed in the open jet of a closed return wind tunnel. The turbine was tested in a three blade and a two blade configuration. The power coefficient of the turbine was measured and wake how studies conducted for a range of yawed flows by tilting the rotor plane at various angles up to 30 degrees to the incident wind direction. The motion of the shed vorticity was followed using laser-sheet flow visualisation with the overall wake deflection being measured. The results were compared with theoretical predictions and with studies conducted elsewhere.